## HW 2.19

Maya Khoury
Posts: 29
Joined: Fri Apr 06, 2018 11:03 am

### HW 2.19

2.9 (a) How many values of the quantum number l are possible when n=7? (b) How many values of ml are allowed for an electron in a 6d-subshell? (c) How many values of ml are allowed for an electron in a 3p-subshell? (d) How many subshells are there in the shell with n=4?

I only understand part a, can someone explain b through d?

Chem_Mod
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### Re: HW 2.19

For part b you are trying to determine the number of ml values in a 6d subshell. So for ml the possible values are any integer from +l to -l. For a subshell 6d, 6 is the value of n, and d is the value for l, where d corresponds to the number 2. So if ml is all the integers from +l to -l then the possible ml values are 2,1,0,-1,-2. This gives a total of 5 possible values for ml.
For part c, you are again looking for the possible ml values, but for a subshell of 3p. For 3p that means n=3 and l=1, so the possible ml values are 1,0,-1 so there are 3 possible ml values.
For part d, it is asking for the number of subshells, or possible l values. For any n value the possible l values are from 0 to n-1, so for n=4 the possible values are from 0 to 3. This gives possible l values of 0, 1, 2, and 3, so the total number of subshells possible are 4.

Zuri Smith 1A
Posts: 34
Joined: Fri Apr 06, 2018 11:05 am

### Re: HW 2.19

For part b, If 6=n, why would l=2? I thought that l could be, at max, n-1.